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		<H3><A name="HDRMEASURE" ></A>Measure</H3>
		<A NAME="IDX589"></A><A NAME="IDX590"></A>
<P><STRONG>Category</STRONG>
<P>
<A HREF="refgu008.htm#HDRCATTRN">Transformation</A>
<A NAME="IDX591"></A>
<P><STRONG>Function</STRONG>
<P>
Performs length, area, and volume measurements on an input object.
<P><STRONG>Syntax</STRONG>
<PRE><STRONG>
output</STRONG> = Measure(<STRONG>input, what</STRONG>);
</PRE>
<P><STRONG>Inputs</STRONG>
<BR>
<TABLE BORDER>
<TR>
<TH ALIGN="LEFT" VALIGN="TOP" WIDTH="20%">Name
</TH><TH ALIGN="LEFT" VALIGN="TOP" WIDTH="20%">Type
</TH><TH ALIGN="LEFT" VALIGN="TOP" WIDTH="20%">Default
</TH><TH ALIGN="LEFT" VALIGN="TOP" WIDTH="40%">Description
</TH></TR><TR>
<TD ALIGN="LEFT" VALIGN="TOP" WIDTH="20%"><TT><STRONG>input</STRONG></TT>
</TD><TD ALIGN="LEFT" VALIGN="TOP" WIDTH="20%">field
</TD><TD ALIGN="LEFT" VALIGN="TOP" WIDTH="20%">none
</TD><TD ALIGN="LEFT" VALIGN="TOP" WIDTH="40%">data to be measured
</TD></TR><TR>
<TD ALIGN="LEFT" VALIGN="TOP" WIDTH="20%"><TT><STRONG>what</STRONG></TT>
</TD><TD ALIGN="LEFT" VALIGN="TOP" WIDTH="20%">string
</TD><TD ALIGN="LEFT" VALIGN="TOP" WIDTH="20%">input dependent
</TD><TD ALIGN="LEFT" VALIGN="TOP" WIDTH="40%">measurement to be performed
</TD></TR></TABLE>
<P><STRONG>Outputs</STRONG>
<BR>
<TABLE BORDER>
<TR>
<TH ALIGN="LEFT" VALIGN="TOP" WIDTH="25%">Name
</TH><TH ALIGN="LEFT" VALIGN="TOP" WIDTH="25%">Type
</TH><TH ALIGN="LEFT" VALIGN="TOP" WIDTH="50%">Description
</TH></TR><TR>
<TD ALIGN="LEFT" VALIGN="TOP" WIDTH="25%"><TT><STRONG>output</STRONG></TT>
</TD><TD ALIGN="LEFT" VALIGN="TOP" WIDTH="25%">value
</TD><TD ALIGN="LEFT" VALIGN="TOP" WIDTH="50%">result of the measurement
</TD></TR></TABLE>
<P><STRONG>Functional Details</STRONG>
<P>
<TABLE CELLPADDING="3">
<TR VALIGN="TOP"><TD><P><B><TT><STRONG>input</STRONG></TT>
</B></TD><TD><P>is the field to be measured.
It is expected to have a "connections" component consisting of
lines, surfaces, or volumes.
</TD></TR><TR VALIGN="TOP"><TD><P><B><TT><STRONG>what</STRONG></TT>
</B></TD><TD><P>specifies the type of measurement to be performed.
<UL COMPACT>
<LI>Unless the parameter value is "element," the module performs a
measurements of the field as a whole.
The structure of the output is identical to that of the input, with
each field (or composite field) replaced by an array containing a
simple scalar floating-point measurement of that field.
<P>
The default value of <TT><STRONG>what</STRONG></TT> is determined by the
"connections"-component element type.
If the connections element type is:
<DL COMPACT>
<DD>"lines," the parameter defaults to "length."
<DD>"triangles" or "quads," the parameter defaults to
"area."
<DD>is "cubes" or "tetrahedra," the parameter defaults to
"volume."
</DL>
<LI>If <TT><STRONG>what</STRONG></TT> is "element," the module performs
element-by-element measurement on <TT><STRONG>input,</STRONG></TT>
replacing the "data" component with scalar arrays
that are connection dependent and contain the
measurement of each
connection element.
If the connections element type is:
<DL COMPACT>
<DD>"lines," the resulting "data" component will contain
the length of each line segment.
<DD>"triangles" or "quads," the resulting "data"
component will contain the area of each triangle or quad.
<DD>is "cubes" or "tetrahedra," the resulting "data"
component will contain the volume of each cube or tetrahedron.
</DL>
</UL>
</TD></TR></TABLE>
<P>
The options for <TT><STRONG>what</STRONG></TT> are shown in the following
table:
<BR>
<P><B><A NAME="Table_7" HREF="refgu002.htm#FT_Table_7">Table 7. Options for
Measure's What Parameter</A></B><BR>
<TABLE BORDER>
<TR>
<TH ALIGN="LEFT" VALIGN="BOTTOM">Connection element
</TH><TH ALIGN="LEFT" VALIGN="BOTTOM">What
</TH><TH ALIGN="LEFT" VALIGN="BOTTOM">Measurement
</TH></TR><TR>
<TD ALIGN="LEFT" VALIGN="TOP" ROWSPAN="3">lines
</TD><TD ALIGN="LEFT" VALIGN="TOP"> "length"
</TD><TD ALIGN="LEFT" VALIGN="TOP"> total length of line segments
</TD></TR><TR><TD ALIGN="LEFT" VALIGN="TOP"> "element"
</TD><TD ALIGN="LEFT" VALIGN="TOP"> length of each line segment
</TD></TR><TR><TD ALIGN="LEFT" VALIGN="TOP"> "area"
</TD><TD ALIGN="LEFT" VALIGN="TOP"> 2-D area enclosed by connected line
segments.
If a series of segments is not closed, a segment connecting the first
and final points of the sequence is added.
</TD></TR><TR>
<TD ALIGN="LEFT" VALIGN="TOP" ROWSPAN="2">faces
</TD><TD ALIGN="LEFT" VALIGN="TOP"> "area"
</TD><TD ALIGN="LEFT" VALIGN="TOP"> total area of all faces
</TD></TR><TR><TD ALIGN="LEFT" VALIGN="TOP"> "element"
</TD><TD ALIGN="LEFT" VALIGN="TOP"> area of each face
</TD></TR><TR>
<TD ALIGN="LEFT" VALIGN="TOP" ROWSPAN="3">triangles, quads
</TD><TD ALIGN="LEFT" VALIGN="TOP"> "area"
</TD><TD ALIGN="LEFT" VALIGN="TOP"> total area of all surface elements
</TD></TR><TR><TD ALIGN="LEFT" VALIGN="TOP"> "element"
</TD><TD ALIGN="LEFT" VALIGN="TOP"> area of each surface element
</TD></TR><TR><TD ALIGN="LEFT" VALIGN="TOP"> "volume"
</TD><TD ALIGN="LEFT" VALIGN="TOP"> 3-D volume enclosed by connected sets of
surface elements.
If a connected set of surface elements is not closed, the approximate
closing surface(s) is(are) found by triangulating the openings in
the surface (defined by loops of unshared edges).
</TD></TR><TR>
<TD ALIGN="LEFT" VALIGN="TOP" ROWSPAN="2">polylines
</TD><TD ALIGN="LEFT" VALIGN="TOP"> "length"
</TD><TD ALIGN="LEFT" VALIGN="TOP"> total length of all lines
</TD></TR><TR><TD ALIGN="LEFT" VALIGN="TOP"> "element"
</TD><TD ALIGN="LEFT" VALIGN="TOP"> length of each line
</TD></TR><TR>
<TD ALIGN="LEFT" VALIGN="TOP" ROWSPAN="2"> tetrahedra, cubes
</TD><TD ALIGN="LEFT" VALIGN="TOP"> "element"
</TD><TD ALIGN="LEFT" VALIGN="TOP"> volume of each 3-D element
</TD></TR><TR><TD ALIGN="LEFT" VALIGN="TOP"> "volume"
</TD><TD ALIGN="LEFT" VALIGN="TOP"> total volume of all 3-D elements
</TD></TR><TR>
<TD ALIGN="LEFT" VALIGN="TOP" COLSPAN="3"><B>Notes&#58; </B>
<OL>
<P><LI>The default value for lines and polylines is "length";
"area" is the default for triangles, quads, and faces;
and "volume" is the default for tetrahedra
and cubes.
<P><LI>All sequences of line segments are handled independently when
measuring area.
Sequences are defined by following exactly identical coordinate points,
rather than by following identical point indices.
Overlapping volumes are not detected.
Similarly for volumes enclosed by surface elements, a volume is defined
by triangles consisting of identical vertex positions, rather
than by triangles consisting of identical point indices.
Overlapping volume is not detected.
<P><LI>Be aware of the following:
Curves are closed by straight lines regardless of the geometry from
which they were derived.
The surfaces added to close volumes are triangulated as if planar.
This module ignores any transforms in the object.
For example, if the object is scaled by 2 (with the Scale module), the
volume will <I>not</I> increase.
</OL>
</TD></TR></TABLE>
<P><STRONG>Example Visual Program</STRONG>
<PRE>
ThunderGlyphSheet.net
</PRE>
<P><STRONG>See Also</STRONG>
<P>
&nbsp;<A HREF="refgu036.htm#HDRCOMPUTE">Compute</A>
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